The design, construction and performance testing of a very high resolution fluorescence laser scanner microscope is a continuation of current research. The high speed scanner (64 Megacycles/wavelength channel) will be completed under current support by December 1987. The high speed scanner will then undergo operational performance testing and the development of operational software will begin. The random access scanner, high light collection optics workstation has been completed in its design, and the optics will be in house be December 1987. The workstation will be built with all of its components. Optical testing during assembly will be done. The scanning module optics will be built, assembled, and tested. The scanning unit will be assessed and tested, and operational software will be written. Final operational testing of the entire workstation will be carried out. The confocal workstation will use commercial microscope optics, and will share the scanning optics with the other station in the random access module. Z-axis scanning will be implemented, and 3-dimensional reconstruction and display software will be written.